.\"	$NetBSD: getpeername.2,v 1.6 1995/10/12 15:40:56 jtc Exp $
.\"
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.\"     @(#)getpeername.2	8.1 (Berkeley) 6/4/93
.\"
.Dd June 4, 1993
.Dt GETPEERNAME 2
.Os BSD 4.2
.Sh NAME
.Nm getpeername
.Nd get address of connected peer
.Sh SYNOPSIS
.Fd #include <sys/socket.h>
.Ft int
.Fo getpeername
.Fa "int socket"
.Fa "struct sockaddr *restrict address"
.Fa "socklen_t *restrict address_len"
.Fc
.Sh DESCRIPTION
The
.Fn getpeername
function returns the address of the peer connected to the specified 
socket. 
.Pp
The
.Fa address_len
parameter should be initialized to indicate
the amount of space pointed to by
.Fa address .
On return it contains the actual size of the address
returned (in bytes).
.Pp
The address is truncated if the buffer provided is too small.
.Sh RETURN VALUES
.Rv -std getpeername
.Sh ERRORS
The call succeeds unless:
.Bl -tag -width Er
.\" ==========
.It Bq Er EBADF
The argument
.Fa socket
is not a valid descriptor.
.\" ==========
.It Bq Er EFAULT
The 
.Fa address
parameter points to memory not in a valid part of the
process address space.
.\" ==========
.It Bq Er EINVAL
.Fa socket
has been shut down.
.\" ==========
.It Bq Er ENOBUFS
Insufficient resources were available in the system
to perform the operation.
.\" ==========
.It Bq Er ENOTCONN
Either the socket is not connected
or it has not had the peer pre-specified.
.\" ==========
.It Bq Er ENOTSOCK
The argument
.Fa socket
refers to something other than a socket (e.g., a file).
.\" ==========
.It Bq Er EOPNOTSUPP
.Fn getpeername
is not supported for the protocol in use by
.Fa socket .
.El
.Sh SEE ALSO
.Xr accept 2 ,
.Xr bind 2 ,
.Xr getsockname 2 ,
.Xr socket 2
.Sh HISTORY
The
.Fn getpeername
function call appeared in
.Bx 4.2 .
